Theories of similarities between Earth and the moon in terms of their material have always attracted scientific interest with most attributing it to the latter's origin from Earth.
But the puzzle persisted on the original source of that material and the timing and mode of its arrival given the perception that Earth was formed by the amalgamation of different masses.
Many scientific models have attributed Earth's composition to the accretion of a slew of masses that ranged from the size of Mars to moon with materials of wide-ranging isotopic properties.
A new research has argued that Earth and the moon are formed from similar materials that are hard to demarcate in the matter of isotopic qualities.
"Earth accreted from an isotopically homogenous reservoir," said Nicolas Dauphas, the Louis Block Professor in Geophysical Sciences and the study's author.
The findings have been published in Nature.
In the research, Dauphas probed the isotopes of material that went into the making of Earth by recreating the formation process and observed a "genetic link" binding the building blocks of the planetary bodies.
The study found stark isotopic similarities in many elements that shaped the different stages of Earth's formation.
According to the research, an evolutionary process followed the making of Earth dating back to 4.5 billion years. It had a growing core that was fed by elements which had a strong liking for metals from the space. Such an accretion of material from space continued even after the saturation of core and they resided in the mantle.
"Before this work, the question of the nature of Earth's accreting material through time was mostly rhetorical," said Dauphas.
Enstatite Meteorites Material
The research mentioned enstatite meteorites — an extraterrestrial material as constituting the bulk material in early stages of Earth with enstatite-type impactors adding to it later on.
Data showed that Earth, the moon, and meteorites had a high concentration of the mineral enstatite whose isotopic compositions were hard to distinguish.
However, when it came to moon's formation, early models of Earth's formation were hard in explaining it well as they harped on Earth's formation by varied materials of diverse isotopic compositions.
"The moon is isotopically similar to Earth," Dauphas said.
That surmise came from the assumption that the impactor that hit Earth and triggered the formation of moon most likely had an identical isotopic composition as Earth.
The finding of the research was hailed as "an elegant approach" thanks to its ability to explain the origin and source of materials that went into the making of Earth.
The theory also shows that the material used in making Earth was "ordered," according to David Stevenson, Caltech's Professor of Planetary Science. The Mars-mass projectile that bombarded Earth must have been similar to Earth and that put an end to the puzzle why Earth and the moon are strikingly similar.
Moon Formation
Meanwhile, a new theory on the formation of Moon has dismantled previous theories and said a series of smaller bodies hit the embryonic Earth that led to a calibrated formation of the moon.
The reigning hypothesis has been asserting that moon formed in a single shot after splintering from Earth under the impact of Earth struck by a Mars-sized asteroid.
In line with the new theory, scientists expect one-fifth of the moon's material having come from Earth and the rest of the impacting body.
The new research is alluding that the impactor asteroid too had materials similar to Earth.
